SUMMARY/Abstract Cancer is one of the leading causes of death in US. It is estimated that there were about 564,800 deaths from cancer in 2017, which was more than 1,500 people per day. The high mortality rate is a direct result of lack of effective early stage clinical diagnosis method and therapeutic stratification. If cancer can be effective detected early and treated with right therapy, the average five years relative survival rate would greatly increase. Extracellular vesicles (EVs), bilayered nano-sized vesicles that are found in all bodily fluids, are emerging as a appealing type of cancer biomarker for non-invasive cancer diagnosis and therapeutic stratification. EVs would provide significant potential benefit for cancer patients that need repetitive tissue biopsy. For example, solid tumors are not accessible in about 49% of advanced or metastatic non-small cell lung cancer (NSCLC) patients. To unleash EVs? great potential in clinical applications, rapid and efficient isolation of EVs is a prerequisite. However, most of current EVs isolation approaches cannot meet the need in clinical settings due to inherent shortcomings (e.g. lengthy procedure, low yield, and low throughput). Additionally, in terms of clinical application of EV in cancer molecular analysis, there is no FDA approved EV-based diagnostic tools available. Captis Diagnostics has developed a new proprietary lipid nanoprobe (LNP) system that can isolate EVs directly from samples (US Application No. 62/430,161 and International Application No. PCT/US2017/064634). The LNP is capable of efficiently isolating EVs from cell culture media or human body fluids (e.g. plasma) using a rapid workflow and inexpensive reagents. In this proposal, we propose to develop and commercialize our lipid nanoprobe system invention for EV isolation from plasma and further develop EV DNA analysis platform for targeted therapy selection in NSCLC patients. For Aim 1, Captis Diagnostics will optimize and validate of the LNP technology to develop it to a research kit for EV isolation that can achieve high EV isolation efficiency, simple and short workflow, and adaption to complex bodily fluids samples, such as blood plasma. Aim 2 will develop a proof-of-concept clinical assay for targeted therapy selection in NSCLC patients by combining mutation detection by digital droplet PCR (ddPCR) with LNP EV isolation . Successful completion of these Aims will yield a proprietary advanced technology and position Captis Diagnostics to pursue clinical validation of the EV in clinical assay for targeted therapy selection for cancer patients. Phase II activities will be focused on the clinical performance of NSCLC targeted therapy selection assays, in which the EV isolation technology will be tested with samples from cancer patients to validate its clinical utility.